1. Field of the Invention
The present invention relates to a clip or fastener used for removably mounting a first structure provided with an insertion rib with an insertion slot to a second structure provided with a mounting opening. Typically, the first structure is a trim piece and the second structure is an instrument panel or other vehicular sub-structure.
2. Description of the Related Art
Trim fastener clips are well known in the vehicular trim and molding art to mount a first structure 200, such as a trim piece to a second vehicular sub-structure 202, such as an instrument panel, by several clips 204 (see FIGS. 18-19 for examples of these mounting configurations).
These types of fastener clips typically comprise a U-shaped member defined by a pair of outer legs which are interconnected by a bight portion allowing flexure of the outer legs about the bight portion. In addition, one or more inner legs typically depend from the bight portion, between the outer legs, and have an inwardly-extending detent thereon.
These types of trim fastener clips are typically mounted on a first structure having an insertion rib provided with an insertion slot by passing the insertion rib between the inner legs until the detent thereon engages within the insertion slot. Thus, the inner legs retain the fastener clip on the insertion rib by the removable engagement of the detent within the insertion slot. In addition, the trim fastener clip is then employed to mount the first structure to a second structure having a mounting opening. The bight portion of the U-shaped member is passed into the mounting opening until lateral edges of the mounting opening of the second structure engage within recesses in the outer legs of the U-shaped member. Thus, the first structure is retained against the second structure by the trim fastener clip. One example of a prior art trim fastener clip in shown in U.S. Pat. Nos. 5,966,782 and 6,119,316 both to Ishihara et al., issued Oct. 19, 1999 and Sep. 19, 2000, respectively.
There remains some problems with the prior art trim fastener clips. First, these types of clips typically employ either a single point-contact stabilization means for the inner legs of the fastener clip to engage the outer surfaces of the insertion rib or planar surfaces on the inner legs which squeezingly contact the outer surfaces of the insertion rib. In either event, the engagement of the inner legs of the fastener clip with the outer surfaces of the insertion rib is either too unstable or, in the case of the use of planar surfaces on the trim fastener clip inner legs, is too difficult and costly to manufacture a clip which has surfaces that are exactly parallel and can grip the outer surfaces of the insertion rib. Second, these types of clips, being somewhat small in size, are difficult to mount on an insertion rib and often the insertion rib becomes lodged between the inner surfaces of an outer legs and an outer surface of the inner leg, rather than between the inner legs as desired. Third, for clips that have a high height-to-width ratio, the outer legs can have too much flexure inherent therein which can cause inadvertent dislodgement of the outer legs of the trim fastener clip from the mounting opening of the second structure. Fourth and finally, the clips are difficult to mount to foam-type sub-structures which have varying sizes, thicknesses and tolerances.
The inventive fastener clip described herein overcomes the limitations of the prior art by providing a fastener clip which is more easily insertable onto an insertion rib having an aperture and is stably maintained in place by a mounting structure on inner legs on the clip which define multiple lines of contact with the insertion rib thereon. The clip also includes guide members which prevent misalignment and mis-mounting of the clip onto an insertion rib by directing an end of the insertion rib between the inner legs of the clip. On clips with a high height-to-width aspect ratio, the invention also contemplates stand-off protrusions mounted on inner surfaces of outer legs on the clip which abut the insertion rib to prevent over-flexure of the outer legs thereof. The invention also contemplates the provision of tensioning ribs on laterally-extending feet on the outer legs of the clip to maintain the feet in tension against a vehicular sub-structure of varying thickness and tolerances.
In one aspect, the invention relates to a fastener for mounting a first structure having an insertion rib with a retention slot to a second structure having a mounting opening comprising a U-shaped body. A bight portion is provided at an upper portion thereof with a pair of outer legs depending therefrom, each of the pair of outer legs having an outer surface adapted to receive an edge of the mounting opening to removably mount the outer legs to the second structure. A pair of inner legs is provided between the pair of outer legs, the pair of inner legs cooperating to define at least in part an elongated channel therebetween having opposing inner surfaces adapted to receive the insertion rib. Each of the inner legs preferably having, at a lower portion thereof, a retainer adapted to be received within the retention slot. An improvement thereof comprises at least one of the inner surfaces of the elongated channel having a variable curvature thereon defining at least two lines of contact with the insertion rib in a spaced vertical relationship.
In various embodiments of the invention, both inner surfaces can have the variable curvature. The variable curvature on one of the inner surfaces can mirror that on the other inner surface. The variable curvature can be undulating with a first radius of curvature, a second radius of curvature, a third radius of curvature and a fourth radius of curvature in alternating convex/concave relationship. The second and fourth radii of curvature can define the at least two points of contact. The second radius of curvature can be approximately ten times as large as the first radius of curvature. The third radius of curvature can be approximately two times as large as the second radius of curvature. The fourth radius of curvature can be approximately four times as large as the third radius of curvature.
The pair of outer legs can extend downwardly to a greater extent than the pair of inner legs; and can further comprise guide members extending from the lower portion of the inner legs downwardly to the outer legs and forming a guide for aligning the insertion rib with the elongated channel as the insertion rib is inserted between the pair of outer legs. The guide members can be flexible and flex with the flexure of the inner and outer legs. The retainer can have a leading edge thereon for camming the inner legs apart during mounting of the fastener onto the insertion rib. The guide member can have a leading edge in planar alignment with the retainer leading edge.
At least one of the pair of outer legs can further comprise a stand-off protrusion extending inwardly a sufficient extent to maintain contact with the insertion rib when the insertion rib is positioned within the elongated channel to prevent inward flexing of the lower portion of the at least one of the pair of outer legs during mounting of the fastener to the second structure and inadvertent overtravel of the fastener relative to the mounting opening thereof. The lower portion of the at least one of the pair of the outer legs can terminate in an outwardly extending flange that is adapted to abut an underside of the second structure when the fastener is mounted to the second structure. The outwardly extending flange can be spaced downwardly from the stand-off protrusion. The guide member can be spaced upwardly from the stand-off protrusion to permit flexure of the outer legs therebetween. The outer legs can have a thin-walled portion between the guide member and the stand-off protrusion to facilitate flexure of the outer legs therebetween. The stand-off protrusions can form a fulcrum for flexure of the pair of outer legs during mounting of the fastener to the second structure. Each of the pair of outer legs can have a stand-off protrusion thereon.
The outer surface of the pair of outer legs can have a shoulder adapted to receive an upper edge of the mounting opening. A lower portion of at least one of the outer legs can terminate in an outwardly extending flange that is adapted to abut an underside of the second structure during mounting of the fastener to the second structure. The outwardly-extending flange can have an upwardly-extending tensioning rib thereon adapted to abut the underside of the second structure to bias the second structure against the shoulder whereby the fastener can be used with second structures of varying thickness and tolerances. The tensioning rib can be located at an outer portion of the outwardly-extending flange. The tensioning rib can be generally semi-circular in cross section.
In another aspect, the invention relates to a fastener for mounting a first structure having an insertion rib with a retention slot to a second structure having a mounting opening comprising a U-shaped body having a bight portion at an upper portion thereof with a pair of outer legs depending therefrom, each of the pair of outer legs having an outer surface adapted to receive an edge of the mounting opening to removably mount the outer legs to the second structure. A pair of inner legs is provided between the pair of outer legs, the pair of inner legs cooperating to define at least in part an elongated channel therebetween having opposing inner surfaces adapted to receive the insertion rib, each of the inner legs having, at a lower portion thereof, a retainer adapted to be received within the retention slot. The improvement of the invention comprising the pair of outer legs can extend downwardly to a greater extent than the pair of inner legs, and further comprising guide members extending from the lower portion of the inner legs downwardly to the outer legs and forming a guide for aligning the insertion rib with the elongated channel as the insertion rib is inserted between the pair of outer legs.
In other embodiments of the invention, the guide members can be flexible and flex with the flexure of the inner and outer legs. The retainer can have a leading edge thereon for camming the inner legs apart during mounting of the fastener onto the insertion rib. The guide member can have a leading edge in planar alignment with the retainer leading edge. The retainer can have a leading edge thereon for camming the inner legs apart during mounting of the fastener onto the insertion rib.
At least one of the pair of outer legs can further comprise a stand-off protrusion extending inwardly a sufficient extent to maintain contact with the insertion rib when the insertion rib is positioned within the elongated channel to prevent inward flexing of the lower portion of the at least one of the pair of outer legs during mounting of the fastener to the second structure and inadvertent overtravel of the fastener relative to the mounting opening thereof. The lower portion of the at least one of the pair of the outer legs can terminate in an outwardly extending flange that is adapted to abut an underside of the second structure when the fastener is mounted to the second structure. The outwardly extending flange can be spaced downwardly from the stand-off protrusion. The guide member can be spaced upwardly from the stand-off protrusion to permit flexure of the outer legs therebetween. The outer legs can have a thin-walled portion between the guide member and the stand-off protrusion to facilitate flexure of the outer legs therebetween. The stand-off protrusions can form a fulcrum for flexure of the pair of outer legs during mounting of the fastener to the second structure. Each of the pair of outer legs can have a stand-off protrusion thereon.
The outwardly-extending flange can have an upwardly-extending tensioning rib thereon adapted to abut the underside of the second structure to bias the second structure against the shoulder whereby the fastener can be used with second structures of varying thickness and tolerances. The tensioning rib can be located at an outer portion of the outwardly-extending flange. The tensioning rib can be generally semi-circular in cross section.
In yet another aspect, the invention relates to a fastener for mounting a first structure having an insertion rib with a retention slot to a second structure having a mounting opening comprising a U-shaped body having a bight portion at an upper portion thereof with a pair of outer legs depending therefrom, each of the pair of outer legs having an outer surface adapted to receive an edge of the mounting opening to removably mount the outer legs to the second structure. A pair of inner legs between the pair of outer legs, the pair of inner legs cooperating to define at least in part an elongated channel therebetween having opposing inner surfaces adapted to receive the insertion rib, each of the inner legs having, at a lower portion thereof, a retainer adapted to be received within the retention slot. The inventive improvement hereof comprising a lower portion of at least one of the pair of outer legs further comprises a stand-off protrusion extending inwardly a sufficient extent to maintain contact with the insertion rib when the insertion rib is positioned within the elongated channel to prevent inward flexing of the lower portion of the at least one of the pair of outer legs during mounting of the fastener to the second structure and inadvertent overtravel of the fastener relative to the mounting opening thereof.
In other embodiments of the invention, the lower portion of the at least one of the pair of the outer legs can terminate in an outwardly extending flange that is adapted to abut an underside of the second structure when the fastener is mounted to the second structure. The outwardly extending flange can be spaced downwardly from the stand-off protrusion. Guide members can extend from the lower portion of the inner legs downwardly to the outer legs and form a guide for aligning the insertion rib with the elongated channel as the insertion rib is inserted between the pair of outer legs. Each guide member can be spaced upwardly from the stand-off protrusion to permit flexure of the outer legs therebetween. The outer legs can have a thin-walled portion between the guide member and the stand-off protrusion to facilitate flexure of the outer legs therebetween. The stand-off protrusions can form a fulcrum for flexure of the pair of outer legs during mounting of the fastener to the second structure. Each of the pair of outer legs can have a stand-off protrusion thereon.
In a further embodiment, a fastener for mounting a first structure having an insertion rib with a retention slot to a second structure having a mounting opening comprising a U-shaped body having a bight portion at an upper portion thereof with a pair of outer legs depending therefrom, each of the pair of outer legs having an outer surface with a shoulder adapted to receive an edge of the mounting opening to removably mount the outer legs to the second structure, wherein a lower portion of at least one of the outer legs terminates in an outwardly extending flange that is adapted to abut an underside of the second structure during mounting of the fastener to the second structure. A pair of inner legs between the pair of outer legs, the pair of inner legs cooperating to define at least in part an elongated channel therebetween having opposing inner surfaces adapted to receive the insertion rib, each of the inner legs having, at a lower portion thereof, a retainer adapted to be received within the retention slot. An improvement thereof comprising the outwardly-extending flange can have an upwardly-extending tensioning rib thereon adapted to abut the underside of the second structure to bias the second structure against the shoulder whereby the fastener can be used with second structures of varying thickness and tolerances.
In other embodiments of the invention, the tensioning rib can be located at an outer portion of the outwardly-extending flange. The tensioning rib can be generally semi-circular in cross section.